I was raised by witnesses. My family name in particular is painfully well-known within the religion. Admittedly, there are minor variations from family to family, based on personal interpretation. (Which the organization works very hard to discourage and limit) And at one point back in the 90's there was chatter about the sovereignty of preserving the body but it was never cemented as 'law' to avoid the distress it may have caused for individuals lost during the holocaust specifically.
I can attest as a former 'golden child' that as an organization, there is no official doctrine against cremation. It's pretty rare for a family to choose burial over cremation.